Lantern or lamp



{No.Model.)

G. W. STOCKLY LANTERN 0R LAMP.

N. Punks, MLMnpw. www", D. c.

UNTTED STATES PATENT GEEICE.

GEORGE lV. STOCKLY, OF CLEVELAND, OlllO.

LANTERN OR LAMP.

SPECIFICATION forming part of Letters Patent lf3. 400,140, dated March26, 1889.

Application tiled September 18, 1888. Serial No, 285,666. (No model.)

To all 107mm/ z'f may concern:

.Be it known that l, GEORGE W. S'rocKLY, ot Cleveland, in the county ofCuyahoga and State oi' Ohio, have invented certain new and usefulImprovements in Lanterns or Lamps; and I do hereby declare the followingto be a full, clear, and exact description of the invention, such aswill enable others skilled in the art to which it appertains to make anduse the same.

My invention rela-tes to la-nterns or lamps vfor photographicdark-rooms, to be used in furnishing a proper amount ot light for thevarious stages in the operation of developing` negatives. The utility ofsuch a lantern or lamp, capable of instantaneous manual adjustment togive any desired variation in the quantity oi illumination furnished byit, will be apparent to all who have worked in photographic dark-rooms.

In the use of modern dry-plates, especially those that are exceedinglysensitive and rapid in action, a very small amount of light is all thatcan be safely used in the dark room while taking such plates out ottheir wrappings and placing them in the plate-holders previous to anexposure in the camera. Similar care and an equally small light arenecessary in taking the plates out of the holders after an exposure andwhile placing them in the developing-pans ready for the application etthe developers. No more light should be used up to this point than isabsolutely necessary to enable the opera-tor to do the work. As soon,however, as the developer has been applied to the dry-plate and theprocess of development has fairly commenced, a little more light cansafely be used, and as the process ot.' development advances more andmore light can safelybe used without. injury to the plates. Thisincreased amount of light is necessary to enable the operator todetermine the proper moment. After the development ls completed and thefixing process which tolinto the dark-room.

lt will be obvious from this brief statement i that a dark-room lanternor lamp which can be instantly adjusted to give a light varyingI to acomparatively bright but non-actinic light must be of value; and it isthe object of my present invention to accomplish this important result;and to this end it consists, generallyspeaking, in a screen ot'non-actinic material, so arranged that various degrees ot,

quantities of light may be transmitted through its several parts, theseehangesin the position of the screen being made by manual means.

In the accompanying drawings, Figure l is a view in side elevation ot'my device, portions of its interior being indicated in dotted lilies.Fig. 2 isa top plan view. Fig. is a sectional view on line fr x, Fig. l.Fig. at is amodification; and Fig. is a view in section on line Y Y,Fig. l.

Obviously, there are many ways ot.' embodying my invention in practicaltorm, and the following constitutes the most feasible.

A represents a practically light-tight box, square or round, as desired,of either wood or metal, and provided with openings o., such openin gsbeing' placed so that light from the inside will be projected in anydesired direction. l have teun d it convenient in constructing lanternsot this character to have two openings at right angles to each other,making it possible to throw a light on the developing apparatus inlfront ot' the lantern, and also on one side of it. The main feature otmy invention consists, however, in a screen, B, of non-actinic coloredpaper, or any other material which admits the passage ot' light.

vThis screen is preferably of cylindrical form,

s0 arrangedv that it will revolve close to the inner wall of the outercasing, A, a crank or handle, c, being furnished this screen andprojecting through the box A,whereby motion may be applied. Thisnon-actinic screen is made in such a way that at one point in itscircumference, or on one side of it, as at E, Fig.

1 3, there is onlyone thickness ot paper or other the progress ot thedevelopment of the latent t nuage and to check. this development at justmaterial, or not unich obstruction to the penetration of light, andtherefore at this point a comparatively large amount ol light will be 3transn'iitted through the screen trom the canlows 1s runder way, stillmore light may be let p dle, lamp, or incandescent electric light L.(Shown in dotted lines in Fig. l Startin g from this point, the paperitself is either gradually increased in thickness, darkened in color,

` treated so that it will admit a greater or less all the way from thedimmest possible light i amount ot' light in plat-es, orz'ulditionallayers FOO may be used, as shown atpoints F, G, and H, Fig. 3, wheretwo, three, and four layers are indicated, so that less and less lightis transmitted through the openings a a as the screen is revolved, untilnally, when the four thicknesses, as at H, are over the opening oropenings, there is very little if any light transmitted. lf an electriclight, L, is used in the interior of the lantern as the source of light,the'entire outside case can be made lighttight except at the openingsreferred to, and where such a light can be obtained it is by far thebest method for this purpose. lf a candle or lamp is to be used as thesource of light in the lantern, suitable arrangements must be made forthe supply of air and the escape of products of combustion.

Another way of embodying my invention would be to construct the screen Bof various colors or various thicknesses or layers of glass or similarmaterial, arranged in panels on the side of a square or hexagonallantern, which can be Aturned in any desired position.

Still another method of embodying the invention would be to provide anoutside case for the lantern, having on one or more sides of it iiXednon-actinic colored screens of any suitable material, as shown in Fig.4, arranged so that, say, at the bottom d the screens would transmit theleast amount of light and at .the top the greatest amount, andintermediate amounts between, and vice versa, and l then provide anoutside. curtain, D, or shutter that claim as new, and desire to secureby Letters v l. In a photographic dark-room lamp or lantern, a framehaving an opening therein, an d a non-actinic screen made in sectionsdiffering in degrees of transparency or translucency to the passage oflight.`

2. In a photographic dark-room lamp or lantern, the combination of asource of light, a screen of non-actinic colored material arranged tointerpose two or more diierent degrees of transparency or translueencyto the passage of light, and an outside case or body provided with oneor more openings through which light can be transmitted from within,substantially as set forth.

3. The combination, with a box or casing having one or more openings, ofa movable cylinder therein, portions of the outside of which are made upof from oney to several different layers of .non-actinic material, and asource of light within the cylinder, substantially as set forth.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

GEORGE WV. STOCKLY.

W'itnesses: y

A. D. DORMAN, L. S. NoLD.

